This blog is dedicated to bringing World War II era tank archives to a wider audience, by translating them into English if necessary and providing some historical context to those unfamiliar with it.
Questions? Requests? Comments? Email me at tankarchives@gmail.com or find me on Twitter @Tank_Archives.

Left: 7 metersBoth of the commander's sights have identical range and dead zones. The variable dead zones in the front, rear, and right parts of the field of view are explained by the geometry of the turret and the rotating portion of the roof."

RGASPI 644-2-464

All of this data is helpfully visualized in a diagram, which also includes data for the loader and driver, who are omitted from the text description.